MikeTbass, Furex and Eben Stone answered the question already, I can reformulate the conclusion the following way:
The measurement results would have been useful with the following modifications:
1. Instead of using a "test substance", use (artificial) skin with (artificial) stubble.
2. Include blades of different geometry / thickness: e.g. SE blades, straights
3. Test the "longevity" of the blades in a uniform way, e.g. cutting duration of a substance for N seconds, then leave unused in comparable storing conditions for M seconds...
I would add some other points:
4. Remove coatings of blades in a reliable, reproducible way (polishing? acidic solutions?). Some DE blades have coatings only on the bevel, while others have the complete blade covered.
5. Multiple measurements have been done with each blade, but the sample size per brand is 1. I can say from personal experience that not all manufacturers have impeccable QA. To illustrate this point: I have never had issues with Med Preps or Feathers. But I once had a batch (approx. 20 blades out of 100) of Rapiras which were not sharpened; I have had rPs sharp on one side only (all 10 blades in a dispenser) and I had a whole package (100) of Astras which had grease marks stretching up to the cutting point. In other words, 1 blade per test doesn't cut it...
The measurement results would have been useful with the following modifications:
1. Instead of using a "test substance", use (artificial) skin with (artificial) stubble.
2. Include blades of different geometry / thickness: e.g. SE blades, straights
3. Test the "longevity" of the blades in a uniform way, e.g. cutting duration of a substance for N seconds, then leave unused in comparable storing conditions for M seconds...
I would add some other points:
4. Remove coatings of blades in a reliable, reproducible way (polishing? acidic solutions?). Some DE blades have coatings only on the bevel, while others have the complete blade covered.
5. Multiple measurements have been done with each blade, but the sample size per brand is 1. I can say from personal experience that not all manufacturers have impeccable QA. To illustrate this point: I have never had issues with Med Preps or Feathers. But I once had a batch (approx. 20 blades out of 100) of Rapiras which were not sharpened; I have had rPs sharp on one side only (all 10 blades in a dispenser) and I had a whole package (100) of Astras which had grease marks stretching up to the cutting point. In other words, 1 blade per test doesn't cut it...
